In the late 13th century A.D., Gregory Chionades travelled from Byzantium to Persia to study mathematics and astronomy. There he learned Persian and Arabic and studied under Shams ad-Din al-Bukhari, who was associated with the Maragha school of Nasir al-Din al-Tusi.
Chioniades translated many works from Arabic and Persian into Greek, and is probably the person responsible for introducing such Islamic innovations as the so-called "Tusi Couple" to the West. (The Tusi couple - a theorem that produces linear motion from a combination of uniform, circular motions - appears without attribution in the De Revolutionibus of Copernicus. The transmission of Tusi's work from Iran to the West is discussed in Otto Neugenauer's History of Ancient Mathematical Astronomy and elsewhere.)
Dr. David Edwin Pingree was planning to edit and translate the surviving works of Chioniades. The first of these, the Zij al-Alai, was published in the 1980's. Dr. Pingree gave me the task of editing and translating what was to have been the second in the series as my doctoral dissertation.
Before beginning the edition of the three surviving Greek manuscripts, I studied the two surviving Arabic manuscripts of the epitome of the Zij as Sanjari of al-Khazini with Dr. Pingree. ( These Arabic manuscripts are available online at http://www.wilbourhall.org. The epitome is doubtless the text Chioniades had in front of him when he made his translation.)
Dr. Pingree then set about teaching me how to edit the three Greek manuscripts in light of the Arabic originals - and in some cases in light of the marginalia of the same, in light of Chioniades' idiosyncratic Greek, and in the light - the blindingly brilliant light - of Dr. Pingree's unspeakably vast knowledge. All editorial decisions regarding either manuscript readings or matters of translation were either made or approved by Dr. Pingree himself. (Correspondingly, all errors the reader may find are mine alone.)
Dr. Pingree then worked with me extensively on the Greek to English translation and the Greek to Arabic glossary until all met with his approval


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